Prototypes & Objects interview questions

1. A.both shallow-copy own enumerable properties; spread {...o} is an expression while Object.assign mutates a target object
2. B.an ES6 class is syntax over JS's prototype-based inheritance, not a separate object model
3. C.the chain of [[Prototype]] links JS walks to resolve a property not found on the object itself
4. D.tests whether a property exists directly on an object rather than being inherited via the prototype chain

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1. A.Prototype chain
2. B.Object.create
3. C.Spread vs Object.assign
4. D.Object.freeze

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1. A.Prototype chain — an ES6 class is syntax over JS's prototype-based inheritance, not a separate object model
2. B.Prototype chain — both shallow-copy own enumerable properties; spread {...o} is an expression while Object.assign mutates a target object
3. C.Prototype chain — the chain of [[Prototype]] links JS walks to resolve a property not found on the object itself
4. D.Prototype chain — creates a new object with its prototype set to the object you pass in

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1. A.an ES6 class is syntax over JS's prototype-based inheritance, not a separate object model
2. B.creates a new object with its prototype set to the object you pass in
3. C.the chain of [[Prototype]] links JS walks to resolve a property not found on the object itself
4. D.tests whether a property exists directly on an object rather than being inherited via the prototype chain

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1. A.Object.freeze
2. B.hasOwnProperty
3. C.Object.create
4. D.class is sugar

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1. A.Object.create — the chain of [[Prototype]] links JS walks to resolve a property not found on the object itself
2. B.Object.create — tests whether a property exists directly on an object rather than being inherited via the prototype chain
3. C.Object.create — both shallow-copy own enumerable properties; spread {...o} is an expression while Object.assign mutates a target object
4. D.Object.create — creates a new object with its prototype set to the object you pass in

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1. A.creates a new object with its prototype set to the object you pass in
2. B.an ES6 class is syntax over JS's prototype-based inheritance, not a separate object model
3. C.the chain of [[Prototype]] links JS walks to resolve a property not found on the object itself
4. D.tests whether a property exists directly on an object rather than being inherited via the prototype chain

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1. A.Spread vs Object.assign
2. B.Object.create
3. C.hasOwnProperty
4. D.class is sugar

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1. A.hasOwnProperty — makes an object immutable at the top level — its own properties cannot be added, deleted, or reassigned
2. B.hasOwnProperty — an ES6 class is syntax over JS's prototype-based inheritance, not a separate object model
3. C.hasOwnProperty — tests whether a property exists directly on an object rather than being inherited via the prototype chain
4. D.hasOwnProperty — both shallow-copy own enumerable properties; spread {...o} is an expression while Object.assign mutates a target object

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1. A.makes an object immutable at the top level — its own properties cannot be added, deleted, or reassigned
2. B.the chain of [[Prototype]] links JS walks to resolve a property not found on the object itself
3. C.an ES6 class is syntax over JS's prototype-based inheritance, not a separate object model
4. D.creates a new object with its prototype set to the object you pass in

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1. A.Object.freeze
2. B.class is sugar
3. C.Spread vs Object.assign
4. D.hasOwnProperty

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1. A.class is sugar — the chain of [[Prototype]] links JS walks to resolve a property not found on the object itself
2. B.class is sugar — creates a new object with its prototype set to the object you pass in
3. C.class is sugar — tests whether a property exists directly on an object rather than being inherited via the prototype chain
4. D.class is sugar — an ES6 class is syntax over JS's prototype-based inheritance, not a separate object model

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1. A.the chain of [[Prototype]] links JS walks to resolve a property not found on the object itself
2. B.makes an object immutable at the top level — its own properties cannot be added, deleted, or reassigned
3. C.an ES6 class is syntax over JS's prototype-based inheritance, not a separate object model
4. D.tests whether a property exists directly on an object rather than being inherited via the prototype chain

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1. A.Object.freeze
2. B.hasOwnProperty
3. C.Object.create
4. D.class is sugar

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1. A.Object.freeze — both shallow-copy own enumerable properties; spread {...o} is an expression while Object.assign mutates a target object
2. B.Object.freeze — creates a new object with its prototype set to the object you pass in
3. C.Object.freeze — makes an object immutable at the top level — its own properties cannot be added, deleted, or reassigned
4. D.Object.freeze — an ES6 class is syntax over JS's prototype-based inheritance, not a separate object model

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1. A.creates a new object with its prototype set to the object you pass in
2. B.makes an object immutable at the top level — its own properties cannot be added, deleted, or reassigned
3. C.the chain of [[Prototype]] links JS walks to resolve a property not found on the object itself
4. D.both shallow-copy own enumerable properties; spread {...o} is an expression while Object.assign mutates a target object

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1. A.Spread vs Object.assign
2. B.hasOwnProperty
3. C.class is sugar
4. D.Object.create

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1. A.Spread vs Object.assign — an ES6 class is syntax over JS's prototype-based inheritance, not a separate object model
2. B.Spread vs Object.assign — both shallow-copy own enumerable properties; spread {...o} is an expression while Object.assign mutates a target object
3. C.Spread vs Object.assign — makes an object immutable at the top level — its own properties cannot be added, deleted, or reassigned
4. D.Spread vs Object.assign — creates a new object with its prototype set to the object you pass in

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